With the advent of the Information Age, conventional cathode ray tube (CRT) displays have been replaced by flat panel displays. One of the most widely used flat panel displays are liquid crystal displays (LCDs), which are featured with proven technology and affordable cost. However, LCDs have technical limitations in terms of contrast, viewing angle, flexibility, and power consumption, etc., because LCDs do not emit light by themselves. Recently, organic light-emitting diodes (OLEDs) are emerging as a new generation of display elements and have attracted a lot of attention, because of their various advantages such as self-luminous, wide viewing angle, fast response, high luminous efficiency, wide color gamut, low operation voltage, thin panel, large size capability and flexibility.
FIG. 1 illustrates a schematic cross-sectional view of an existing OLED display panel. As shown in FIG. 1, the existing OLED display panel includes a substrate (not drawn in FIG. 1), and a light-emitting unit formed on the substrate. The light-emitting unit comprises a transparent anode 7, a cathode 1 composed of a metal or an alloy, and a plurality of organic thin films sandwiched between the anode 7 and the cathode 1. The organic thin films are often categorized in terms of functions. A hole injection layer (HIL) 6, a hole transport layer (HTL) 5, a light-emitting layer (EML) 4, an electron transport layer (ETL) 3, and an electron injection layer (EIL) 2 are often sequentially disposed on the anode 7. Certain OLED display panel also comprises a hole blocking layer (HBL), and an electron blocking layer (EBL), etc.
However, in the existing OLED display panel, some holes in one pixel may flow laterally to adjacent pixels, causing the adjacent pixels to emit light. That is, the lateral leakage is serious. In addition, the hole and electron transport balance in the OLED display panel is highly desired to be improved, thereby improving the luminous efficiency and reducing the power consumption of the OLED display panel.
The disclosed OLED display panel, fabrication method and electronic device thereof are directed to solve one or more problems set forth above and other problems.